The flashing arrow panel is one of the most effective and riveting traffic control devices used in work zones, clearly broadcasting the message lane closed ahead. This program describes correct use of flashing arrow panels to indicate lane closure for highway construction work zones. The video discusses mode selections (arrow, chevron, or caution; flashing or sequential), panel design standards for given traffic speeds and volumes, lamp brightness, sign height, and power supply. Stationary, moving, day-time and night-time installations are shown. Applications and appropriate placement in conjunction with other traffic control devices are shown for single and multiple lane closures, center-lane work areas, and shoulder closures. Situations best suited for flashing arrow panels, as well as situations where they should not be used, are described. Costs and maintenance are discussed, and the program's recommendations are summarized.